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UiS Subsea University of Stavanger

Stavanger, Norway

MATE 2019

Kim Jamal Alstad (Mentor) Chairman (CEO)/Power distribution Lukas Neuenschwander Vice Chairman/Software Tolunay Metli Head of Finances Oscar Holmås Co. head of sponsorships/Mechanical design Arne Steinnes Co. head of sponsorships/Propulsion and manipulator Mai-Linn Aarvold Head of Marketing Greta Bekerytè Power distribution Heiki Henrichsen Software Thomas Duus Propulsion and manipulator Andres Runestad Sensors and signal processing Hedly Berg Nilsen Sensors and signal processing Jon Erik Bjerga Micro-ROV Elzat Kadeer Micro-ROV

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Table of contents I. Introduction .......................................................................................................................................... 4

A.Abstract ............................................................................................................................................ 4

II. Safety ................................................................................................................................................... 4

A. Safety Philosophy ............................................................................................................................ 4

B. Lab Safety Protocol .......................................................................................................................... 4

C. Vehicle Safety Features ................................................................................................................... 4

Mechanical ...................................................................................................................................... 4

Electrical .......................................................................................................................................... 5

III. Design Rationale ................................................................................................................................. 5

A. Design Proscess ............................................................................................................................... 5

B. Power Distribution .......................................................................................................................... 6

C. Sensor Board ................................................................................................................................... 7

D. Motor Controllers ........................................................................................................................... 8

E. Thrusters .......................................................................................................................................... 8

F. Frame ............................................................................................................................................... 8

G. Camera ............................................................................................................................................ 9

Camera Mount ................................................................................................................................ 9

Seconday Camera .......................................................................................................................... 10

Additional Cameras ....................................................................................................................... 10

H. Manipulator .................................................................................................................................. 10

I. Electronic Housing .......................................................................................................................... 10

J. Tether ............................................................................................................................................. 11

IV. Mission Tools .................................................................................................................................... 11

A.Overview ........................................................................................ Feil! Bokmerke er ikke definert.

B.Lift Bag Tool .................................................................................................................................... 11

C. Tool to Level the OBS .................................................................... Feil! Bokmerke er ikke definert.

C. Inductive Power ............................................................................. Feil! Bokmerke er ikke definert.

V. Software Design ................................................................................................................................ 11

A. Overview ....................................................................................................................................... 11

B.Control Station ............................................................................................................................... 12

C. Tether Communication ................................................................................................................. 12

D.Internal Communication ................................................................................................................ 13

E. Movement Controls ....................................................................................................................... 13

VI. Logistics ............................................................................................................................................ 13

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A. Company Organization .................................................................................................................. 13

B.Project management ...................................................................................................................... 14

C. Budget and Project Costing ........................................................................................................... 14

VII. Conclusion ....................................................................................................................................... 16

A. Testing and Troubleshooting ........................................................................................................ 16

B. Challenges ..................................................................................................................................... 17

C. Lessons Learned and Skills Gained ................................................................................................ 17

D.Future Improvements .................................................................................................................... 18

E. Reflections ..................................................................................................................................... 18

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I. Introduction A.Abstract UiS Subsea has through 2019 developed the ROV to perform a variety of tasks in this year’s competition in Kingsport, Tennessee. The project group consists of 13 hardworking bachelor students from the University in Stavanger, with diverse backgrounds. Our vision for Rån has been to build a small and versatile ROV which can perform the challenges in the competition fast.

UIS Subsea is a student organization under the University in Stavanger which yearly develops

a new ROV. The organizations goal is to give bachelor students an opportunity to acquire

knowledge about underwater engineering projects and to use theory in practice. This year’s

ROV-team consists of ten electrical engineering students and one mechanical engineering

student. Rån is designed to be as small as possible to be fast and easy to navigate. The

electrical housing is designed so that all the custom printed circuit boards, motor controllers

and cameras have enough room to allow air circulation to prevent high temperatures. The

frame is made of aluminum to be light and strong enough to carry the eight thrusters,

electrical housing and the manipulator.

II. Safety

A. Safety Philosophy

At UiS Subsea, safety is top priority. This company follows a zero-tolerance approach when it comes to safety risks. The company and the University of Stavanger have numerous guidelines to mitigate damage or serious illness to the people in the working environment. UiS Subsea utilizes working JSAs for both operating and producing. To accommodate our HSE protocols, we have our own designated HSE coordinator. Some of our electrical – engineers (Bachelor students) who are working on and constructing Rån are certified electricians with experience and attention to workmanship. Since they were used to handling tools and filling out JSAs it became natural for them to oversee and advise work done by others.

B. Lab Safety Protocol Everyone involved in manufacturing has undergone lab-safety courses. As a result, the team can operate any machines necessary for their work in a safely and functionally manner. This corresponds with the company’s and the University’s zero tolerance approach to safety risks. Different safety equipment is mandatory for the different work environments. Safety goggles are always required, and ear protections are required for noisy environments. Proper ventilation and use of respiratory equipment are mandatory in environments involving dust and microparticles.

C. Vehicle Safety Features

Mechanical

The tether has been equipped with a strain-relief made of aramid to prevent any damages to the connectors if the tether is exposed to strain. The tether is also sleeved to prevent any damage to the cables. All sharp edges have been deburred to ensure safe operation and

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handling. All the thruster has been fitted with thruster guards that holds IP 20, to ensure that no particles less than 12.5 mm (typically a finger) will be shredded by the propeller.

Electrical

The electrical components are protected with fuses. These are dimensioned according to

operating currents. There is one fuse in the tether less than 30 cm from the power supply,

there are also a main fuse inside the ROV, resettable fuses for the motors and ordinary fuses

for the rest. The vehicle is equipped with a button that shuts of the power to the motors

manually. Additionally, if the communication is lost, all power to the motors will shut off.

III. Design Rationale

A. Design Process The company began the product development phase by brainstorming the team’s ideas and designs. We did this by breaking down the competition manual [1] to see what the tasks demanded from both the mechanical- and electro department. The company used brainstorming in between the different groups of engineering students to come up with good solutions. We did this to discover things that could not be done, e.g. that the mechanical engineering had a design that wouldn’t be possible to accomplish, because of the electrical parts that had to be adopted into the robot. The company looked for ways to improve our previously ROVs, along with the future goals for Rån. After the requirements for the mission was released, the main factors for the design were identified, which was weight and size. To meet the specifications, it was necessary to discuss the materials and designs out of what we thought was most appropriate for the competition. With these new requirements and target specifications defined, different concepts were generated in order, by using a concept scoring matrix with respect to the requirements. The scores were added and the best concept was selected for further development. It was

decided that Rån would only have one electronics housing with specified dimensions to

minimize weight and size. In addition, we decided to improve the previous design by

implementing a dome at the front of the housing. From this approach the team had a

starting point for the rest of the ROV. It was then possible for the team to work in parallel,

ensuring a rapid development. Precautions were taken regarding electromagnetic

interference that occurred from choosing one housing. To minimize this problem, circuit

boards and connectors were placed in ways that high and low power electronics could be

separated as much as possible. This concept would require few connectors, which lead to a

less total volume and a reduced production cost. Next, with the help of different CAD tools

and FEA-simulations we got a physical understanding on how the final design would look

like. The different components were generated digitally into CAD files using Autodesk

Inventor. The CAD files were then prepared for machining by making a program for

fabricating in the CNC machine. For components made in the 3D printer, the format was

converted to a stl file.

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Figure 1:3D drawing of ROV.

B. Power Distribution All the subsystems in Rån is powered through a power distribution board. The power distribution board has been specially designed for this ROV and contains all the voltage regulators and safety features required for normal operation.

Figure 2: Power distribution board with heat sink and cooling fan.

The inlet cable is connected to the bard 15 cm from the power supply attachment point. The inlet power (40-65V) is converted to 5 V and 12 V via three DC/DC-converters. The board inlet and each subsystem have individual fuses.

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Figure 3: Front and back side of the power distribution board.

Each thruster motor is designed to deliver up to 135W of power, and the manipulator

motors 135W. For a total of 1440W of power, its total power consumption is limited by

software to accommodate a power supply of 800W.

C. Sensor Board Rån is equipped with a tailor-made sensor board, designed with intent of easy expansion and compatibility. It has spare ports with the possibility of connecting extra sensor if needed. When it comes to navigating in deep and sludgy oceans with little to no visibility, the ROV is dependent on its many sensors.

Figure 4: Sensor board to the ROV.

Rån is therefore equipped with the following sensors to help her guide through the water. • Pressure sensor used to calculate the depth from the surface. • Sensors for information about the ROVs orientation • Leakage sensors in case of water breaking through the housing • Temperature sensor to keep an eye on the temperature inside

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• Power usage sensors on all motors to identify errors, and distributing the power in the most efficient way Together, all these sensors ensure a robust and reliable ROV, and making it possible to lock

the ROV in any desirable orientation.

D. Motor Controllers The fitting for the motor controllers were designed with free airflow and optimal use of space in mind. To ensure optimal performance by the motors and motor controllers, there is used high – end capacitor with very low ESR. This allows the DC/DC converter to maintain a very stable voltage at startup as well as during operation. For each motor controller there is mounted plugs on the wires for the supply voltage and for the motors to ensure easy decoupling in case of replacement and troubleshooting. The circuit board holders in figure 5 are designed with a heatsink, so that the MOSFETs at the motor controllers, will have a large surface to get rid of heat.

Figure 5: The fitting for the motor controllers and capacitors.

E. Thrusters Rån uses eight thrusters, where the design of the propellers, and the shrouding with thruster guards are self-made. The shrouds and thruster guards were produced using the additive manufacturing process known as fused deposition modelling, FDM. Having unlimited access to the university’s 3D-printer during this process, the shrouds were cost-effective and easily produced. For vertical control of Rån, four thrusters were mounted in the corners, on the inside of the frame. As for the horizontal control, the four remaining thrusters were also mounted in the corners, but on the outside. To make it easier to achieve 6 degrees of freedom, the horizontal thrusters were mounted at 45-degree angles. The company therefore decided to implement picatinny rails into the thruster system design. Picatinny rails allows for quick detachment and reattachment.

All eight thrusters use the motor, Series 28-30A from NTM Prop Drive. At maximum thrust,

the motor use 20 A at 12 V and each thruster could produce over 34 N. The motor was

sponsored by JM-robotics.

F. Frame Rån’s frame is built to be light and to help make the ROV easy to maneuver. The placement of the electronics house is set to be in the center of the ROV. The frame therefore consists of four aluminum U-profiles, two under and one on each side, designed to surround half of the electronics housing. The U-profiles were chosen due to their low weight, low cost, availability, and easy processing. They also serve as cushioning for the electronics house. The thrusters are integrated into the frame, both on the outside and the inside of the frame and are therefore

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placed far from the center. This gives better maneuverability and provides enough torque when the ROV has eccentric loads. Having the electronics house in the center along with the increased torque, makes the frame ideal for the 6 degrees of freedom navigation system. The headlights are potted in optically clear epoxy, using a mold made from aluminum to

mount the headlights in place. This solution requires minimal space and weight.

Figure 6: The ROV frame.

G. Camera

Camera Mount

This year’s ROV concept has been mounted with a dome in the front. This improvement from last year’s design has the benefit of placing the main camera inside the dome, giving a better viewing angle. The main camera will be mounted in a 3D modelled camera housing made out of Polyactic Acid (PLA), with the smart functionality of 360-degree free rotation. Two servomotors will be directly mounted on the camera housing providing the tilting and the panning of the camera inside the dome. The benefits of using servomotors is the programmable interface that can prevent the camera from being rotated beyond components that blocks the view for the camera (Manipulator, frame, etc.). The camera and the camera house will be mounted on a plate made from aluminum inside

the pod of the ROV. This type of solution will give an easy maneuvering of the camera, and

the structural strength, holding everything in place.

Figure 7: The camera mounting rigg.

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Seconday Camera

A secondary camera has been strategically placed under the ROVs manipulator giving the most crucial viewing angle, as most of the task will be performed by the manipulator, furthermore the tools that will be used solving the task given by the pilot are also occupying the same area as the manipulator, namely, in the front of the ROV.

By placing a camera with a slightly wider lens, such the manipulator and the tools are in sight has proven us that this is just what’s needed in case the main camera is not enough. Choosing an analog FPV camera will give the least error sources, since the transmission cables will go uninterrupted from the ROV to the topside computers through the tether.

Additional Cameras

Rån has been mounted with additional cameras for a better functionality. An USB camera

will monitor the tether in the back of the ROV, and one in the front as an overall tool

camera. They will be connected to the ASUS Tinkerboard inside the pod, giving us the option

to mount even more cameras where it will be essentially needed.

H. Manipulator The manipulator was designed with focus on weight, durability and modularity. To reduce

weight, the manipulator and end effector is powered by 3 brushless DC motors, Multistar

Elite 3508-268KV, potted in epoxy instead of stepper motors. This solution avoids the need

for waterproof housings, but introduces the need for gearing, as the RPM of the motors is

relatively high. Rån’s manipulator system consists of 3 functions, which are; a wrist with

pitch and roll and an end effector equipped with an intermeshing 2-finger gripper. The

different functions can be locked in place manually in the event of failure. The 3-function

gripper enables the ROV to grab and place objects, both in front of Rån and on the seabed,

move objects around and turn handles on each corner of the OBS. The manipulator is

controlled by the surface control system.

Figure 8: The manipulator

I. Electronic Housing All the main electronics for Rån are located inside an acrylic tube sealed with a custom CNC milled aluminum endcap and front cap. The main purpose of the electronic housing is to keep the electronics dry, safe and easily accessible.

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A dome is placed on the front cap for the camera to see trough. The tube is held in place by two rods connected to the aluminum frame. For construction of the tube, acrylic material where chosen because of its lightweight and high-strength properties. It is also an advantage that the electronics housing is transparent when driving Rån, so it’s possible to inspect the status LED indicators on the circuit boards and wiring without opening the housing. The housing shape makes it hydrodynamic which makes it easier for the pilot to maneuver in

water. The air volume gives buoyance to the ROV system reducing the need of extra floating.

Figure 9: 3D-model of the electronic housing

J. Tether Rån’s tether contains power and communication cables neatly bundled into a flexible, protective sleeve with strain relief on both ends. The tether contains: - 2*2.5mm2 flexible single stranded tinned core for power transfer. The power cables are sized for minimal weight and are calculated to be enough for the maximal power needed by Rån. - CAT6 for Ethernet communication to the IP-camera. CAT6 was chosen due to its cost, flexibility and ability to transfer data with a bandwidth of Gbit/sec; which was necessary for streaming the IP-camera video feed. - 2*24 AWG for CAN-bus communication; calculated from bus length and number of nodes. - Air hose for supplying air for the lift bag.

IV. Mission Tools

A. Lift Bag Tool While testing Rån it was discovered that the thrusters didn’t have enough force to lift the

canon. We mounted a lifting bag on the ROV, which will be filled with air by a manual pump,

to compensate for extra force need.

V. Software Design

A. Overview We wanted to build an architecture that would to its full extent utilize the strengths

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available in current technology, while simultaneously maintaining the possibility to easily debug or add extensions to facilitate new requirements or ideas. Going with this mindset we were able to build a system that’s tailored to the task at hand, but still easy to adapt to other projects. By utilizing Git and GitHub this system was built quickly by multiple developers working on different parts of the project, while the entire history of the software was recorded.

B.Control Station This is the surface-side software. From this graphical user interface, the pilot is able to control the ROV using a game-style controller of their own choice. Information about the server, tool readings, and warnings are displayed in near real time, and all the ROV’s settings and configurations are easily accessible. This year the entire user interface was built using HTML, JavaScript and CSS, along with the React JS framework. This made it possible to package the entire user interface within a single webpage, meaning that the user only needs a computer with a working web browser to control the ROV. Whenever the user generates some data - i.e. change some settings or press a button on the controller - an event is triggered. This event will immediately send information about the event to the server over established WebSockets. This results in a very low latency transmission which only consumes strictly necessary resources, as opposed to continuously sending information - that may not contain any changes - with predetermined intervals. Different pilots may have different preferences as to what assignments buttons on the game controller should have. In the controller settings menu it is possible to configure every button and axis on the controller in whatever way it suits the pilot best. Such configurations may then be given a name and stored on the server. Stored configurations will immediately be accessible to all clients.

C. Tether Communication Communication through the tether is made possible by a CAT6 ethernet cable, enabling gigabit bandwidth. To better utilize this feature there is a gigabit ethernet switch inside the ROV to which both Tinkerboards and multiple IP-cameras are connected. Video streams from

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cameras connected to the Tinkerboards are suspended and resumed whenever they are needed. The IP-cameras do this automatically. Data about user controls or sensors in the ROV is packaged with the popular JSON-format and communicated between server and clients using WebSockets.

D.Internal Communication There are two Tinkerboards inside the ROV. The first one is serving as the main server from which the webpage with the user interface is hosted. This Tinkerboard is also responsible for communicating with motor controllers over CAN-bus. The other Tinkerboard is utilizing the

I2C-protocol to communicate with the power supply board and the sensors board. Onboard

GPIO (General Purpose Input Output) pins on this Tinkerboard are used to control lights and servo motors for the main camera by generating PWM-signals.

E. Movement Controls The ROV can be controlled by a range of different game controllers. The button and axis layouts for different controllers can easily be encoded using the JSON-format, which in turn the graphical user interface is able to visualize and manipulate. By default, the only such configuration available is on the XBOX 360 controller. Torque vectors from the controller are transformed individually to make them less sensitive to user input close to extreme points, i.e. close to -100%, 0% or 100%. The data from these raw sources are then mapped to torque around and along all spatial axes. At this point the torque vector is six-dimensional, and it is here that regulator algorithms for depth and angles contribute their own torques. This vector is then transformed to the responding torque on each thruster, resulting in an eight-dimensional vector which is normalized on the interval (-1, 1).

VI. Logistics

A. Company Organization UIS Subsea consists of 13 students, all with different backgrounds from STEM-fields. On the top of the hierarchy, a board of students with and without experience from earlier participation in the competition monitors the economic aspects and the overall health of the company. The project manager is responsible for the daily management, and to oversee that the project is consistently moving forward towards the intermediate objectives. The project manager is also in charge of the two manufacturing and design groups divided into an electrical and a mechanical department. Project manager and chief executive officer (CEO) also work closely with the chief financial officer (CFO). This is so the projects spending is kept within the budget. You can see the budget in the figure on next page. Throughout our time in UiS Subsea, we have not kept a strong hierarchically organizational

structure. Because UiS Subsea consists of a relatively small team and everyone can

participate in other divisions of the company as we see fit. This especially true for the project

manager and the senior department.

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B.Project management To ensure that the project keeps up with its internal and external deadlines, weekly

meetings have been held by the project manager with the whole project team and (a Gantt

chart has been followed. In the meetings each group have presented its progress and had a

chance to ask questions. The Gantt chart makes it easy to follow the projects state and to

give an overlook on objectives that needs to be done in near and far future. All the

employees were in the same room, which paved the way for cross-functional collaboration.

This made sure that both the senior department and the rest of the company had a constant

flow of knowledge and experience across all the departments. This way, the newest

members of the company can quickly get accustomed to working in this company while also

learning about the management aspect of the company, which they in turn can bring this

knowledge to new students next year. This way of transferring knowledge is a tried and

tested methodology and has worked excellently throughout the years. It increases overall

skill of the company with each iteration of vehicle.

C. Budget and Project Cost

The team based its new design principle on last year’s design; hence it was sensible for management

to base this year’s budget on last year’s result and donated funds and leftover capital. The goal was

to make more efficient use of funds as previous expertise could help reveal areas where costs could

be cut while still maintaining optimal quality. As all research is based on cumulative knowledge, the

team looked at ways to improve the previous design principle to increase performance. The budget

of 2019 is given in table 1.

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Table 1: Budget 2019

From previous experience, travel costs tend to vary drastically depending on the destination of the

competition, hence a fair amount of funds were reserved especially for this. We are very grateful for

the support of our sponsors; the University of Stavanger, Subsea 7 Tekna, FFU, Gassco and

Oceaneering for their monetary donations, as well as JM robotics, MacArtey, IKM Technology,

Innova, Elprint and Nexans for their software and material contribution. The table 2 shows the

sponsors and the corresponding values they provided.

Table 2: Company donations

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The spending was strictly controlled and recorded by logging receipts in a spreadsheet. This ensured

to keep the project within budget, as shown in table 3.

Table 3: List of expenses.

VII. Conclusion

A. Testing and Troubleshooting Testing and troubleshooting have been a crucial part in the whole process of creating a brand new ROV. The system functionality is verified through testing of individual components, circuits, and by overall integration. Before entering the water, basic checks and functionality tests were performed by powering the ROV outside the water. After successfully ensuring proper thruster and tool operation and no leakage into the electrical housing, the ROV and equipment were transported to the pool for in-water testing. At the pool, the launch procedure consisted of very careful inspection to verify waterproofing, tether strain relief and

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buoyancy. Initially when the ROV is entering the water the waterproofing test consists of carefully looking for air bubbles coming from the electronic housing and leakage into the pod. Finally, when the ROV was ready, the further testing consisted of mission simulation, getting driving experience and gathering data for further vehicle development.

B. Challenges Throughout the design and build process, many challenges were faced by employees at UiS Subsea. One of the biggest non-technical challenge was the management and collaborating between electrical and mechanical department in both the design and build process. This year there was decided that the size of the electrical housing should be smaller in diameter. That has given a lot of challenges that requires very good communicating and collaborating skill between the departments. Another challenge has been lack of mechanical employees and for that reason some of the electrical crew has also been working with mechanical tasks. To make sure all parts fits as it should and results in good solutions with great details there has been organized weekly meetings to ensure good planning and communications between the departments. The main technical challenge faced was also the fact mentioned that the size of the electrical housing should be smaller in diameter. To do so the design needed to be more compact than ever before, and that has led to many challenges. One of the biggest was the design of the circuit board for power distribution and the result from this challenge was some very interesting PCB designs.

C. Lessons Learned and Skills Gained Each employee of UiS Subsea learned a variety of technical skills. The electrical department employees learned how to start with technical requirements, devise the needed circuit, create a test circuit, and then design the schematic and board layout in Altium. This cumulated in learning how to populate and test the circuit boards. Both mechanical and electrical departments learned the features of Autodesk Inventor, and correct design for manufacturability. Employees also gained skills in manufacturing methods by making their own parts in-house. The software department learned how to make the whole system more portable, making it less dependent on a specific rig, and rather making it possible to connect to any device with an internet connection and an ethernet port. They also learned how to make the software more module based, making it far easier to changes in Rån, or to match any individual preferences. This is a pioneering design for UiS Subsea, making troubleshooting, debugging and redesigning the whole system an easy step in the future. In addition to technical skills, many lessons were learned and employees from every department learned how to work together and communicate with eyes towards a common goal. For the management some of the challenges have been to coordinate the task such that the workload is shared evenly, and to maintain good communication between the departments. During weekly meetings between department leads and project group heads, the previous week’s progress, outstanding tasks, and any new tasks were discussed. This was discovered to have an impact on ensuring appropriate progress was being made in a timely manner and to ensure communications between the departments.

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D. Future Improvements This year saw many improvements from previous year, but there are still many areas to improve. One of our biggest issues this year was lack of employees with mechanical background and for that reason the frame design is about the same as before. Therefor one of the future improvements for the next year will be a new and more compact frame design. Also, one of our future goals is to use sonar system to collect data about ROVs position on the horizontal plane.

E. Reflections UiS Subsea’s number one goal is to promote knowledge and experience about underwater robotics at the University of Stavanger. Since our first participation six years ago, UiS Subsea have facilitated interdisciplinary collaboration through exciting and innovative working environments for its members.

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VIII. Appendix

A. Systems Interconnect Diagram (SID)

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B. Safety Checklist Pre – launch 1. Make sure that the designated working and deployment area is tidy and suited as a proper working environment in accordance with the company’s HSE protocols 2. Ensure that the SJA is filled out and approved by the HSE - coordinator 3. Personal safety equipment ON 4. Ensure that all O-rings are in place, undamaged and properly greased 5. Ensure that no bulkhead connectors are loose 6. Check that all locking sleeves are tightened in place 7. Ensure that the blind plug is fastened tight 8. Check that the electronics housing is fastened 9. Check that all horizontal thrusters are properly fastened with clevis pins 10. Check that all propellers are fastened and in place 11. Ensure that all thruster guards are in place, properly fastened and undamaged 12. Check all exterior cables and connection points for damage, and make sure that they are properly fastened and not in contact with any sharp edges 13. Make sure that all components in the electronic house are properly fastened with no exposed wires or visible damages 14. Make sure that all visible wires and plugs inside the electronic house are properly connected or terminated 15. Keep hands of the ROV before turning power ON 16. Control voltage level and current limiting of power supply if applicable 17. Control status indicator LED’s 18. Do not let the electronics house be closed with power ON above water for a long period of time due to heat accumulation inside the electronic housing 19. Do not run motors in open air for a longer period of time due to possible overheating Launch 1. Keep hands away from thrusters 2. No hands on the control system 3. A minimum of two people launching the ROV 4. Slowly launch Rån 5. Keep Rån calmly under water for 10s, check for bubbles 6. Pull Rån up from water. Inspect waterproof housings for leakages 7. Tether assistance ready 8. Slowly launch Rån Post – launch 1. Power OFF and wait for 5 seconds 2. Pull Rån up 3. Check for major damages 4. Rinse ROV with fresh water, especially underneath propellers and in places where pool – water is accumulated.

UIS Subsea would like to thank everyone who has helped us during the project. A special thanks to our sponsors, mentors and MATE for hosting the competition.

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[1]: (MATE COMPETITION MANUAL. 2019. ”marinetech.” Accessed 2019. marinetech.org.)